The single plate connection, or shear tab, is one of the simple shear connections set out in Part 10 of the AISC Manual, and a fabricator favourite because it is the cheapest of the group: one plate, one weld line, one bolt group.
A placa é sempre soldada ao suporte e normalmente aparafusado em campo para a viga de conexão. It can be welded to the beam instead on a shop-assembled frame. What you should not do is put that weld in the field: field welding is labour-intensive and expensive next to running a bolt in.
Dois tipos de configuração
Which configuration you are in decides which rules apply, and it follows from the geometry rather than from a setting you choose.
-
Configuração convencional
- Apenas uma única linha vertical de parafusos é permitida. O número de parafusos na conexão deve estar entre 2 e 12.
- A distância da linha do parafuso à linha de solda deve ser igual ou menor que 3-1/2 no.
- furos padrão (DST) ou orifícios horizontais com fenda curta (HSSL) são permitidos para serem usados conforme observado na Tabela 10-9 da 15ª edição do manual AISC.
- A distância da borda vertical deve satisfazer os requisitos da Tabela J3.4 da Especificação AISC. A distância horizontal da aresta deve ser maior ou igual a 2d tanto para a placa quanto para a alma da viga, onde d é o diâmetro do parafuso.
- Tanto a espessura da placa quanto a espessura da alma da viga devem atender ao requisito de espessura máxima dado na Tabela 10-9 da 15ª edição do manual AISC.
-
Configuração Estendida
- O número de parafusos não é limitado.
- A distância da linha de solda até a linha do parafuso mais próxima do suporte não é limitada.
- O uso de furos deve atender aos requisitos da Seção J3.2 da Especificação AISC.
- As distâncias das bordas horizontais e verticais devem atender aos requisitos da Tabela de Especificação AISC J3.4.
Designing a Single Plate Connection in SkyCiv
The design code can be AISC 360-16 ASD ou LRFD, and units English/Imperial or SI/Metric. Orientation is BCF, BCW ou BBW; hover the tooltip for what each one means. Clique no “Placa Única” telha.
Guia Detalhes
Record the project details here. None of it changes the calculations, but it carries into the report.
Aba de montagem
Three tabs sit under Assembly: the Girder, the Beam, and the Connection, which holds the single plate.
Guia Viga
Specify the section and material grade of the supporting member. A992 and A36 are in the list; for anything else choose Custom and enter Fy and Fu.
Aba de Feixe
The same inputs for the beam, plus cope dimensions, beam clearance and the difference in elevation.
For BBW orientation the coping is worked out automatically, and you can override it. The automatic cope recalculates whenever you change the beam section, the girder section, the clearance or the difference in elevation.
The clearance is also what puts you in one configuration or the other. A clearance small enough that the beam still sits inside the girder will usually give a conventional single plate, unless the girder flange is wide enough that the distance from the bolt to the girder web exceeds 3-1/2″. A clearance that puts the beam completely outside the girder flange gives an extended single plate. For the difference in elevation, a positive value means the beam is above the girder and a negative value below.
Aba Conexão
Set the plate properties: grade A36 or A992, or Custom with your own Fy and Fu, then the plate width ‘b’, height ‘h’ and thickness ‘thk’.
Watch the 3D renderer as you go. The plate height should sit within the beam depth, and the plate width has to be wide enough for the beam to bolt or weld to, which matters most in an extended configuration.
Luminária 1 Aba
Luminária 1 is the plate to beam web connection. It can be bolted or welded; this walkthrough uses bolted.
Primeiro, the bolt hole types at the beam and at the plate. Fabricators usually ask for standard holes (DST) in the beam and horizontal short-slotted holes (HSSL) in the plate, which buys fitting tolerance in the field. Note that those two are also the only hole types the conventional configuration permits, so reaching for oversized holes moves you into the extended configuration rules.
A continuação, the bolt material or grade: A307, A325, A490 or Custom. A325 and A490 are grades within ASTM F3125, which consolidated the older standalone specifications. Choose N or X for a bearing-type connection and SC for slip-critical.
Slip-critical joints have lower design bolt capacity than bearing-type, so use them where slip actually matters: oversized or slotted holes, load reversal, or fatigue. Between N and X, X gives the larger bolt shear capacity, but the threads must be excluded from the shear plane, and the erector has to know that. Between SC(A) and SC(B), SC(B) gives the larger capacity and requires a more thoroughly prepared faying surface, for example SSPC-SP6 commercial blast cleaning.
Then the bolt diameter, from 5/8″ to 1-1/2″ or the metric equivalents, and the arrangement, até 12 linhas e colunas de parafuso, with the row and column spacing.
Worth knowing: if you need more bolt group capacity, opening up the spacing can do it instead of adding bolts, as long as the plate height still fits within the beam depth. The bolt group strength uses the instantaneous centre of rotation method (ICOR), so a wider spacing is credited with the capacity it actually provides. Check with your fabricator first, though. Many prefer 3″ spacing typical throughout.
A “Beira” input is the distance from the beam end to the first bolt column.
Durar, the erection gap. This is the gap that lets the beam be dropped into place on site. It costs capacity, so specify it only where erection actually needs it.
Luminária 2 Aba
Luminária 2 is the plate to support connection, whether that support is a girder web, a column flange or a column web. For a single plate this is welded only.
Specify the weld material, or ‘Custom’ with your own Fnw if the electrode is not listed, then the weld size. For single plate connections the weld needs to be at least 5/8 vezes a espessura da placa, so that the weld develops the plate.
That rule has a cost consequence worth planning around. Tabela 8-12 da 15ª Edição do Manual AISC, página 8-126, shows a large jump in weld passes between 5/16″ and 3/8″ filé: 5/16″ needs a single pass, 3/8″ needs three. A 1/2″ plate needs only a 5/16″ fillet to develop it, which keeps you in single-pass territory. So if the connection is short of capacity, increase the plate height to the maximum allowable before you increase the thickness. A thicker plate demands a larger weld, and a larger weld means more passes, more deposited metal and more labour time.
Guia de Cargas
Enter the vertical shear under ‘Fy’.
Match the load to the design method you picked at the start. LRFD takes factored loads against design strength; ASD takes service loads against allowable strength. The software cannot tell which you typed.
Guia Resultados
Clique “Executar verificações de design”. Anything missing from the earlier tabs is flagged here rather than silently defaulted.
The summary shows whether the connection passed, with a utilization ratio against each check. Se falhou, change the inputs on the earlier tabs and click “Executar novamente verificações de design”. When it passes, “View Calculation Report” opens the detailed report.
That is an extract from the report. Each check carries its reference to the AISC manual or specification, and the working follows the order the specification uses, so a reviewing engineer can read it line by line instead of reverse-engineering a number.
Aqui está uma cópia em PDF do relatório de cálculo detalhado completo: Relatório de Projeto de Conexão.
Try It Yourself
Pick the single plate, enter your sections, plate and shear, and see every check with its code reference. Ele roda no navegador, sem nada para instalar.
See also the single plate connection calculator, a double angle calculator, quanto pelo Etapas para projetar overview.
